It is, to begin with, a normal and commonplace phenomenon of scholarly discourse that people would hold varying viewpoints when they come to study and discuss the world view of great historical figures such as Sun Yat-sen. What is noteworthy, however, is that if such studies stem from different points of departure, then there are bound to be major differences in their various conclusions. What should we take as a point of departure in our study of Sun Yat-sen's world view? Should it be the ready-made conclusions of the "classical authors" of Marxism and Mao Zedong Thought? Or should it be the realities of Sun Yat-sen's world view, serving as an object of [the study of] history of philosophy? This is the first major problem to be resolved in the area of methodology. Concretely speaking, was Sun's world view materialist or idealist? On this question Comrade Mao Zedong once made a pertinent evaluation. He said: "The cosmology contained in the Three People's Principles is what is called the minsheng view of history; in substance it is dualistic, or idealist" . What attitude ought we to hold vis a vis this assessment if we were to approach it from the angle of Marxist methodology? First of all, we should study in earnest and in detail the entirety of Comrade Mao Zedong's Xin minzhu zhuyi as well as other relevant writings so as to be clear about the precise connotations of the aforementioned assessment. At the same time, we must seriously learn Comrade Mao Zedong's own premises, viewpoints, and methods in studying Sun Yat-sen's world view. Comrade Mao Zedong said that we must not "learn only to quote one-sidedly the individual terminologies used by Marx or Engels or Lenin or Stalin and fail to make use of their premises, view-points, and methods" . It therefore goes without saying that we naturally also ought to apply Comrade Mao Zedong's own criteria in dealing with his own writings. If we were to take simply one conclusion expressed in his writings as the point of departure and failed to take historical reality as our point of departure, we would be violating the spirit of Marxism and Mao Zedong Thought